xref: /freebsd/sys/net80211/ieee80211_wds.c (revision 2f6a179eb910129fb812c1ad1bdc300da1203dc0)
1 /*-
2  * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #ifdef __FreeBSD__
28 __FBSDID("$FreeBSD$");
29 #endif
30 
31 /*
32  * IEEE 802.11 WDS mode support.
33  */
34 #include "opt_inet.h"
35 #include "opt_wlan.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/mbuf.h>
40 #include <sys/malloc.h>
41 #include <sys/kernel.h>
42 
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/endian.h>
46 #include <sys/errno.h>
47 #include <sys/proc.h>
48 #include <sys/sysctl.h>
49 
50 #include <net/if.h>
51 #include <net/if_media.h>
52 #include <net/if_llc.h>
53 #include <net/ethernet.h>
54 
55 #include <net/bpf.h>
56 
57 #include <net80211/ieee80211_var.h>
58 #include <net80211/ieee80211_wds.h>
59 #include <net80211/ieee80211_input.h>
60 
61 static void wds_vattach(struct ieee80211vap *);
62 static int wds_newstate(struct ieee80211vap *, enum ieee80211_state, int);
63 static	int wds_input(struct ieee80211_node *ni, struct mbuf *m,
64 	    int rssi, int noise, uint32_t rstamp);
65 static void wds_recv_mgmt(struct ieee80211_node *, struct mbuf *,
66 	    int subtype, int rssi, int noise, u_int32_t rstamp);
67 
68 void
69 ieee80211_wds_attach(struct ieee80211com *ic)
70 {
71 	ic->ic_vattach[IEEE80211_M_WDS] = wds_vattach;
72 }
73 
74 void
75 ieee80211_wds_detach(struct ieee80211com *ic)
76 {
77 }
78 
79 static void
80 wds_vdetach(struct ieee80211vap *vap)
81 {
82 	if (vap->iv_bss != NULL) {
83 		/* XXX locking? */
84 		if (vap->iv_bss->ni_wdsvap == vap)
85 			vap->iv_bss->ni_wdsvap = NULL;
86 	}
87 }
88 
89 static void
90 wds_vattach(struct ieee80211vap *vap)
91 {
92 	vap->iv_newstate = wds_newstate;
93 	vap->iv_input = wds_input;
94 	vap->iv_recv_mgmt = wds_recv_mgmt;
95 	vap->iv_opdetach = wds_vdetach;
96 }
97 
98 static int
99 ieee80211_create_wds(struct ieee80211vap *vap, struct ieee80211_channel *chan)
100 {
101 	struct ieee80211com *ic = vap->iv_ic;
102 	struct ieee80211_node_table *nt = &ic->ic_sta;
103 	struct ieee80211_node *ni, *obss;
104 
105 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_WDS,
106 	     "%s: creating link to %s on channel %u\n", __func__,
107 	     ether_sprintf(vap->iv_des_bssid), ieee80211_chan2ieee(ic, chan));
108 
109 	/* NB: vap create must specify the bssid for the link */
110 	KASSERT(vap->iv_flags & IEEE80211_F_DESBSSID, ("no bssid"));
111 	/* NB: we should only be called on RUN transition */
112 	KASSERT(vap->iv_state == IEEE80211_S_RUN, ("!RUN state"));
113 
114 	if ((vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0) {
115 		/*
116 		 * Dynamic/non-legacy WDS.  Reference the associated
117 		 * station specified by the desired bssid setup at vap
118 		 * create.  Point ni_wdsvap at the WDS vap so 4-address
119 		 * frames received through the associated AP vap will
120 		 * be dispatched upward (e.g. to a bridge) as though
121 		 * they arrived on the WDS vap.
122 		 */
123 		IEEE80211_NODE_LOCK(nt);
124 		obss = NULL;
125 		ni = ieee80211_find_node_locked(&ic->ic_sta, vap->iv_des_bssid);
126 		if (ni == NULL) {
127 			/*
128 			 * Node went away before we could hookup.  This
129 			 * should be ok; no traffic will flow and a leave
130 			 * event will be dispatched that should cause
131 			 * the vap to be destroyed.
132 			 */
133 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_WDS,
134 			    "%s: station %s went away\n",
135 			    __func__, ether_sprintf(vap->iv_des_bssid));
136 			/* XXX stat? */
137 		} else if (ni->ni_wdsvap != NULL) {
138 			/*
139 			 * Node already setup with a WDS vap; we cannot
140 			 * allow multiple references so disallow.  If
141 			 * ni_wdsvap points at us that's ok; we should
142 			 * do nothing anyway.
143 			 */
144 			/* XXX printf instead? */
145 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_WDS,
146 			    "%s: station %s in use with %s\n",
147 			    __func__, ether_sprintf(vap->iv_des_bssid),
148 			    ni->ni_wdsvap->iv_ifp->if_xname);
149 			/* XXX stat? */
150 		} else {
151 			/*
152 			 * Committed to new node, setup state.
153 			 */
154 			obss = vap->iv_bss;
155 			vap->iv_bss = ni;
156 			ni->ni_wdsvap = vap;
157 		}
158 		IEEE80211_NODE_UNLOCK(nt);
159 		if (obss != NULL) {
160 			/* NB: deferred to avoid recursive lock */
161 			ieee80211_free_node(obss);
162 		}
163 	} else {
164 		/*
165 		 * Legacy WDS vap setup.
166 		 */
167 		/*
168 		 * The far end does not associate so we just create
169 		 * create a new node and install it as the vap's
170 		 * bss node.  We must simulate an association and
171 		 * authorize the port for traffic to flow.
172 		 * XXX check if node already in sta table?
173 		 */
174 		ni = ieee80211_node_create_wds(vap, vap->iv_des_bssid, chan);
175 		if (ni != NULL) {
176 			obss = vap->iv_bss;
177 			vap->iv_bss = ieee80211_ref_node(ni);
178 			ni->ni_flags |= IEEE80211_NODE_AREF;
179 			if (obss != NULL)
180 				ieee80211_free_node(obss);
181 			/* give driver a chance to setup state like ni_txrate */
182 			if (ic->ic_newassoc != NULL)
183 				ic->ic_newassoc(ni, 1);
184 			/* tell the authenticator about new station */
185 			if (vap->iv_auth->ia_node_join != NULL)
186 				vap->iv_auth->ia_node_join(ni);
187 			if (ni->ni_authmode != IEEE80211_AUTH_8021X)
188 				ieee80211_node_authorize(ni);
189 
190 			ieee80211_notify_node_join(ni, 1 /*newassoc*/);
191 			/* XXX inject l2uf frame */
192 		}
193 	}
194 
195 	/*
196 	 * Flush pending frames now that were setup.
197 	 */
198 	if (ni != NULL && IEEE80211_NODE_WDSQ_QLEN(ni) != 0) {
199 		int8_t rssi, noise;
200 
201 		IEEE80211_NOTE(vap, IEEE80211_MSG_WDS, ni,
202 		    "flush wds queue, %u packets queued",
203 		    IEEE80211_NODE_WDSQ_QLEN(ni));
204 		ic->ic_node_getsignal(ni, &rssi, &noise);
205 		for (;;) {
206 			struct mbuf *m;
207 
208 			IEEE80211_NODE_WDSQ_LOCK(ni);
209 			_IEEE80211_NODE_WDSQ_DEQUEUE_HEAD(ni, m);
210 			IEEE80211_NODE_WDSQ_UNLOCK(ni);
211 			if (m == NULL)
212 				break;
213 			/* XXX cheat and re-use last rstamp */
214 			ieee80211_input(ni, m, rssi, noise, ni->ni_rstamp);
215 		}
216 	}
217 	return (ni == NULL ? ENOENT : 0);
218 }
219 
220 /*
221  * Propagate multicast frames of an ap vap to all DWDS links.
222  * The caller is assumed to have verified this frame is multicast.
223  */
224 void
225 ieee80211_dwds_mcast(struct ieee80211vap *vap0, struct mbuf *m)
226 {
227 	struct ieee80211com *ic = vap0->iv_ic;
228 	struct ifnet *parent = ic->ic_ifp;
229 	const struct ether_header *eh = mtod(m, const struct ether_header *);
230 	struct ieee80211_node *ni;
231 	struct ieee80211vap *vap;
232 	struct ifnet *ifp;
233 	struct mbuf *mcopy;
234 	int err;
235 
236 	KASSERT(ETHER_IS_MULTICAST(eh->ether_dhost),
237 	    ("%s not mcast", ether_sprintf(eh->ether_dhost)));
238 
239 	/* XXX locking */
240 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
241 		/* only DWDS vaps are interesting */
242 		if (vap->iv_opmode != IEEE80211_M_WDS ||
243 		    (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY))
244 			continue;
245 		/* if it came in this interface, don't send it back out */
246 		ifp = vap->iv_ifp;
247 		if (ifp == m->m_pkthdr.rcvif)
248 			continue;
249 		/*
250 		 * Duplicate the frame and send it.  We don't need
251 		 * to classify or lookup the tx node; this was already
252 		 * done by the caller so we can just re-use the info.
253 		 */
254 		mcopy = m_copypacket(m, M_DONTWAIT);
255 		if (mcopy == NULL) {
256 			ifp->if_oerrors++;
257 			/* XXX stat + msg */
258 			continue;
259 		}
260 		ni = ieee80211_find_txnode(vap, eh->ether_dhost);
261 		if (ni == NULL) {
262 			/* NB: ieee80211_find_txnode does stat+msg */
263 			ifp->if_oerrors++;
264 			m_freem(mcopy);
265 			continue;
266 		}
267 		if (ieee80211_classify(ni, mcopy)) {
268 			IEEE80211_DISCARD_MAC(vap,
269 			    IEEE80211_MSG_OUTPUT | IEEE80211_MSG_WDS,
270 			    eh->ether_dhost, NULL,
271 			    "%s", "classification failure");
272 			vap->iv_stats.is_tx_classify++;
273 			ifp->if_oerrors++;
274 			m_freem(mcopy);
275 			ieee80211_free_node(ni);
276 			continue;
277 		}
278 		mcopy->m_flags |= M_MCAST | M_WDS;
279 		mcopy->m_pkthdr.rcvif = (void *) ni;
280 
281 		IFQ_HANDOFF(parent, mcopy, err);
282 		if (err) {
283 			/* NB: IFQ_HANDOFF reclaims mbuf */
284 			ifp->if_oerrors++;
285 			ieee80211_free_node(ni);
286 		} else
287 			ifp->if_opackets++;
288 	}
289 }
290 
291 /*
292  * Handle DWDS discovery on receipt of a 4-address frame in
293  * ap mode.  Queue the frame and post an event for someone
294  * to plumb the necessary WDS vap for this station.  Frames
295  * received prior to the vap set running will then be reprocessed
296  * as if they were just received.
297  */
298 void
299 ieee80211_dwds_discover(struct ieee80211_node *ni, struct mbuf *m)
300 {
301 	struct ieee80211vap *vap = ni->ni_vap;
302 	struct ieee80211com *ic = ni->ni_ic;
303 	int qlen, age;
304 
305 	IEEE80211_NODE_WDSQ_LOCK(ni);
306 	if (!_IF_QFULL(&ni->ni_wdsq)) {
307 		/*
308 		 * Tag the frame with it's expiry time and insert
309 		 * it in the queue.  The aging interval is 4 times
310 		 * the listen interval specified by the station.
311 		 * Frames that sit around too long are reclaimed
312 		 * using this information.
313 		 */
314 		/* XXX handle overflow? */
315 		/* XXX per/vap beacon interval? */
316 		/* NB: TU -> secs */
317 		age = ((ni->ni_intval * ic->ic_lintval) << 2) / 1024;
318 		_IEEE80211_NODE_WDSQ_ENQUEUE(ni, m, qlen, age);
319 		IEEE80211_NODE_WDSQ_UNLOCK(ni);
320 
321 		IEEE80211_NOTE(vap, IEEE80211_MSG_WDS, ni,
322 		    "save frame, %u now queued", qlen);
323 	} else {
324 		vap->iv_stats.is_dwds_qdrop++;
325 		_IF_DROP(&ni->ni_wdsq);
326 		IEEE80211_NODE_WDSQ_UNLOCK(ni);
327 
328 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_WDS,
329 		    mtod(m, struct ieee80211_frame *), "wds data",
330 		    "pending q overflow, drops %d (len %d)",
331 		    ni->ni_wdsq.ifq_drops, ni->ni_wdsq.ifq_len);
332 
333 #ifdef IEEE80211_DEBUG
334 		if (ieee80211_msg_dumppkts(vap))
335 			ieee80211_dump_pkt(ic, mtod(m, caddr_t),
336 			    m->m_len, -1, -1);
337 #endif
338 		/* XXX tail drop? */
339 		m_freem(m);
340 	}
341 	ieee80211_notify_wds_discover(ni);
342 }
343 
344 /*
345  * Age frames on the WDS pending queue. The aging interval is
346  * 4 times the listen interval specified by the station.  This
347  * number is factored into the age calculations when the frame
348  * is placed on the queue.  We store ages as time differences
349  * so we can check and/or adjust only the head of the list.
350  * If a frame's age exceeds the threshold then discard it.
351  * The number of frames discarded is returned to the caller.
352  */
353 int
354 ieee80211_node_wdsq_age(struct ieee80211_node *ni)
355 {
356 #ifdef IEEE80211_DEBUG
357 	struct ieee80211vap *vap = ni->ni_vap;
358 #endif
359 	struct mbuf *m;
360 	int discard = 0;
361 
362 	IEEE80211_NODE_WDSQ_LOCK(ni);
363 	while (_IF_POLL(&ni->ni_wdsq, m) != NULL &&
364 	     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
365 		IEEE80211_NOTE(vap, IEEE80211_MSG_WDS, ni,
366 			"discard frame, age %u", M_AGE_GET(m));
367 
368 		/* XXX could be optimized */
369 		_IEEE80211_NODE_WDSQ_DEQUEUE_HEAD(ni, m);
370 		m_freem(m);
371 		discard++;
372 	}
373 	if (m != NULL)
374 		M_AGE_SUB(m, IEEE80211_INACT_WAIT);
375 	IEEE80211_NODE_WDSQ_UNLOCK(ni);
376 
377 	IEEE80211_NOTE(vap, IEEE80211_MSG_WDS, ni,
378 	    "discard %u frames for age", discard);
379 #if 0
380 	IEEE80211_NODE_STAT_ADD(ni, wds_discard, discard);
381 #endif
382 	return discard;
383 }
384 
385 /*
386  * IEEE80211_M_WDS vap state machine handler.
387  */
388 static int
389 wds_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
390 {
391 	struct ieee80211com *ic = vap->iv_ic;
392 	struct ieee80211_node *ni;
393 	enum ieee80211_state ostate;
394 	int error;
395 
396 	IEEE80211_LOCK_ASSERT(ic);
397 
398 	ostate = vap->iv_state;
399 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s\n", __func__,
400 		ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
401 	vap->iv_state = nstate;			/* state transition */
402 	callout_stop(&vap->iv_mgtsend);		/* XXX callout_drain */
403 	if (ostate != IEEE80211_S_SCAN)
404 		ieee80211_cancel_scan(vap);	/* background scan */
405 	ni = vap->iv_bss;			/* NB: no reference held */
406 	error = 0;
407 	switch (nstate) {
408 	case IEEE80211_S_INIT:
409 		switch (ostate) {
410 		case IEEE80211_S_SCAN:
411 			ieee80211_cancel_scan(vap);
412 			break;
413 		default:
414 			break;
415 		}
416 		if (ostate != IEEE80211_S_INIT) {
417 			/* NB: optimize INIT -> INIT case */
418 			ieee80211_reset_bss(vap);
419 		}
420 		break;
421 	case IEEE80211_S_SCAN:
422 		switch (ostate) {
423 		case IEEE80211_S_INIT:
424 			ieee80211_check_scan_current(vap);
425 			break;
426 		default:
427 			break;
428 		}
429 		break;
430 	case IEEE80211_S_RUN:
431 		if (ostate == IEEE80211_S_INIT) {
432 			/*
433 			 * Already have a channel; bypass the scan
434 			 * and startup immediately.
435 			 */
436 			error = ieee80211_create_wds(vap, ic->ic_curchan);
437 		}
438 		break;
439 	default:
440 		break;
441 	}
442 	return error;
443 }
444 
445 /*
446  * Process a received frame.  The node associated with the sender
447  * should be supplied.  If nothing was found in the node table then
448  * the caller is assumed to supply a reference to iv_bss instead.
449  * The RSSI and a timestamp are also supplied.  The RSSI data is used
450  * during AP scanning to select a AP to associate with; it can have
451  * any units so long as values have consistent units and higher values
452  * mean ``better signal''.  The receive timestamp is currently not used
453  * by the 802.11 layer.
454  */
455 static int
456 wds_input(struct ieee80211_node *ni, struct mbuf *m,
457 	int rssi, int noise, uint32_t rstamp)
458 {
459 #define	SEQ_LEQ(a,b)	((int)((a)-(b)) <= 0)
460 #define	HAS_SEQ(type)	((type & 0x4) == 0)
461 	struct ieee80211vap *vap = ni->ni_vap;
462 	struct ieee80211com *ic = ni->ni_ic;
463 	struct ifnet *ifp = vap->iv_ifp;
464 	struct ieee80211_frame *wh;
465 	struct ieee80211_key *key;
466 	struct ether_header *eh;
467 	int hdrspace, need_tap;
468 	uint8_t dir, type, subtype, qos;
469 	uint16_t rxseq;
470 
471 	if (m->m_flags & M_AMPDU) {
472 		/*
473 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
474 		 * w/ M_AMPDU marked have already passed through here
475 		 * but were received out of order and been held on the
476 		 * reorder queue.  When resubmitted they are marked
477 		 * with the M_AMPDU flag and we can bypass most of the
478 		 * normal processing.
479 		 */
480 		wh = mtod(m, struct ieee80211_frame *);
481 		type = IEEE80211_FC0_TYPE_DATA;
482 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
483 		subtype = IEEE80211_FC0_SUBTYPE_QOS;
484 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
485 		goto resubmit_ampdu;
486 	}
487 
488 	KASSERT(ni != NULL, ("null node"));
489 
490 	need_tap = 1;			/* mbuf need to be tapped. */
491 	type = -1;			/* undefined */
492 
493 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
494 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
495 		    ni->ni_macaddr, NULL,
496 		    "too short (1): len %u", m->m_pkthdr.len);
497 		vap->iv_stats.is_rx_tooshort++;
498 		goto out;
499 	}
500 	/*
501 	 * Bit of a cheat here, we use a pointer for a 3-address
502 	 * frame format but don't reference fields past outside
503 	 * ieee80211_frame_min w/o first validating the data is
504 	 * present.
505 	 */
506 	wh = mtod(m, struct ieee80211_frame *);
507 
508 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
509 	    IEEE80211_FC0_VERSION_0) {
510 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
511 		    ni->ni_macaddr, NULL, "wrong version %x", wh->i_fc[0]);
512 		vap->iv_stats.is_rx_badversion++;
513 		goto err;
514 	}
515 
516 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
517 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
518 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
519 
520 	/* NB: WDS vap's do not scan */
521 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_addr4)) {
522 		IEEE80211_DISCARD_MAC(vap,
523 		    IEEE80211_MSG_ANY, ni->ni_macaddr, NULL,
524 		    "too short (3): len %u", m->m_pkthdr.len);
525 		vap->iv_stats.is_rx_tooshort++;
526 		goto out;
527 	}
528 	/* NB: the TA is implicitly verified by finding the wds peer node */
529 	if (!IEEE80211_ADDR_EQ(wh->i_addr1, vap->iv_myaddr) &&
530 	    !IEEE80211_ADDR_EQ(wh->i_addr1, ifp->if_broadcastaddr)) {
531 		/* not interested in */
532 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
533 		    wh->i_addr1, NULL, "%s", "not to bss");
534 		vap->iv_stats.is_rx_wrongbss++;
535 		goto out;
536 	}
537 	IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
538 	ni->ni_noise = noise;
539 	ni->ni_rstamp = rstamp;
540 	if (HAS_SEQ(type)) {
541 		uint8_t tid = ieee80211_gettid(wh);
542 		if (IEEE80211_QOS_HAS_SEQ(wh) &&
543 		    TID_TO_WME_AC(tid) >= WME_AC_VI)
544 			ic->ic_wme.wme_hipri_traffic++;
545 		rxseq = le16toh(*(uint16_t *)wh->i_seq);
546 		if ((ni->ni_flags & IEEE80211_NODE_HT) == 0 &&
547 		    (wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
548 		    SEQ_LEQ(rxseq, ni->ni_rxseqs[tid])) {
549 			/* duplicate, discard */
550 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
551 			    wh->i_addr1, "duplicate",
552 			    "seqno <%u,%u> fragno <%u,%u> tid %u",
553 			    rxseq >> IEEE80211_SEQ_SEQ_SHIFT,
554 			    ni->ni_rxseqs[tid] >> IEEE80211_SEQ_SEQ_SHIFT,
555 			    rxseq & IEEE80211_SEQ_FRAG_MASK,
556 			    ni->ni_rxseqs[tid] & IEEE80211_SEQ_FRAG_MASK,
557 			    tid);
558 			vap->iv_stats.is_rx_dup++;
559 			IEEE80211_NODE_STAT(ni, rx_dup);
560 			goto out;
561 		}
562 		ni->ni_rxseqs[tid] = rxseq;
563 	}
564 	switch (type) {
565 	case IEEE80211_FC0_TYPE_DATA:
566 		hdrspace = ieee80211_hdrspace(ic, wh);
567 		if (m->m_len < hdrspace &&
568 		    (m = m_pullup(m, hdrspace)) == NULL) {
569 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
570 			    ni->ni_macaddr, NULL,
571 			    "data too short: expecting %u", hdrspace);
572 			vap->iv_stats.is_rx_tooshort++;
573 			goto out;		/* XXX */
574 		}
575 		if (dir != IEEE80211_FC1_DIR_DSTODS) {
576 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
577 			    wh, "data", "incorrect dir 0x%x", dir);
578 			vap->iv_stats.is_rx_wrongdir++;
579 			goto out;
580 		}
581 		/*
582 		 * Only legacy WDS traffic should take this path.
583 		 */
584 		if ((vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0) {
585 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
586 			    wh, "data", "%s", "not legacy wds");
587 			vap->iv_stats.is_rx_wrongdir++;/*XXX*/
588 			goto out;
589 		}
590 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1))
591 			ni->ni_inact = ni->ni_inact_reload;
592 		/*
593 		 * Handle A-MPDU re-ordering.  The station must be
594 		 * associated and negotiated HT.  The frame must be
595 		 * a QoS frame (not QoS null data) and not previously
596 		 * processed for A-MPDU re-ordering.  If the frame is
597 		 * to be processed directly then ieee80211_ampdu_reorder
598 		 * will return 0; otherwise it has consumed the mbuf
599 		 * and we should do nothing more with it.
600 		 */
601 		if ((ni->ni_flags & IEEE80211_NODE_HT) &&
602 		    subtype == IEEE80211_FC0_SUBTYPE_QOS &&
603 		    ieee80211_ampdu_reorder(ni, m) != 0) {
604 			m = NULL;
605 			goto out;
606 		}
607 	resubmit_ampdu:
608 
609 		/*
610 		 * Handle privacy requirements.  Note that we
611 		 * must not be preempted from here until after
612 		 * we (potentially) call ieee80211_crypto_demic;
613 		 * otherwise we may violate assumptions in the
614 		 * crypto cipher modules used to do delayed update
615 		 * of replay sequence numbers.
616 		 */
617 		if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
618 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
619 				/*
620 				 * Discard encrypted frames when privacy is off.
621 				 */
622 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
623 				    wh, "WEP", "%s", "PRIVACY off");
624 				vap->iv_stats.is_rx_noprivacy++;
625 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
626 				goto out;
627 			}
628 			key = ieee80211_crypto_decap(ni, m, hdrspace);
629 			if (key == NULL) {
630 				/* NB: stats+msgs handled in crypto_decap */
631 				IEEE80211_NODE_STAT(ni, rx_wepfail);
632 				goto out;
633 			}
634 			wh = mtod(m, struct ieee80211_frame *);
635 			wh->i_fc[1] &= ~IEEE80211_FC1_WEP;
636 		} else {
637 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
638 			key = NULL;
639 		}
640 
641 		/*
642 		 * Save QoS bits for use below--before we strip the header.
643 		 */
644 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
645 			qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
646 			    ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
647 			    ((struct ieee80211_qosframe *)wh)->i_qos[0];
648 		} else
649 			qos = 0;
650 
651 		/*
652 		 * Next up, any fragmentation.
653 		 */
654 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
655 			m = ieee80211_defrag(ni, m, hdrspace);
656 			if (m == NULL) {
657 				/* Fragment dropped or frame not complete yet */
658 				goto out;
659 			}
660 		}
661 		wh = NULL;		/* no longer valid, catch any uses */
662 
663 		/*
664 		 * Next strip any MSDU crypto bits.
665 		 */
666 		if (key != NULL && !ieee80211_crypto_demic(vap, key, m, 0)) {
667 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
668 			    ni->ni_macaddr, "data", "%s", "demic error");
669 			vap->iv_stats.is_rx_demicfail++;
670 			IEEE80211_NODE_STAT(ni, rx_demicfail);
671 			goto out;
672 		}
673 
674 		/* copy to listener after decrypt */
675 		if (bpf_peers_present(vap->iv_rawbpf))
676 			bpf_mtap(vap->iv_rawbpf, m);
677 		need_tap = 0;
678 
679 		/*
680 		 * Finally, strip the 802.11 header.
681 		 */
682 		m = ieee80211_decap(vap, m, hdrspace);
683 		if (m == NULL) {
684 			/* XXX mask bit to check for both */
685 			/* don't count Null data frames as errors */
686 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
687 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
688 				goto out;
689 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
690 			    ni->ni_macaddr, "data", "%s", "decap error");
691 			vap->iv_stats.is_rx_decap++;
692 			IEEE80211_NODE_STAT(ni, rx_decap);
693 			goto err;
694 		}
695 		eh = mtod(m, struct ether_header *);
696 		if (!ieee80211_node_is_authorized(ni)) {
697 			/*
698 			 * Deny any non-PAE frames received prior to
699 			 * authorization.  For open/shared-key
700 			 * authentication the port is mark authorized
701 			 * after authentication completes.  For 802.1x
702 			 * the port is not marked authorized by the
703 			 * authenticator until the handshake has completed.
704 			 */
705 			if (eh->ether_type != htons(ETHERTYPE_PAE)) {
706 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
707 				    eh->ether_shost, "data",
708 				    "unauthorized port: ether type 0x%x len %u",
709 				    eh->ether_type, m->m_pkthdr.len);
710 				vap->iv_stats.is_rx_unauth++;
711 				IEEE80211_NODE_STAT(ni, rx_unauth);
712 				goto err;
713 			}
714 		} else {
715 			/*
716 			 * When denying unencrypted frames, discard
717 			 * any non-PAE frames received without encryption.
718 			 */
719 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
720 			    (key == NULL && (m->m_flags & M_WEP) == 0) &&
721 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
722 				/*
723 				 * Drop unencrypted frames.
724 				 */
725 				vap->iv_stats.is_rx_unencrypted++;
726 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
727 				goto out;
728 			}
729 		}
730 		/* XXX require HT? */
731 		if (qos & IEEE80211_QOS_AMSDU) {
732 			m = ieee80211_decap_amsdu(ni, m);
733 			if (m == NULL)
734 				return IEEE80211_FC0_TYPE_DATA;
735 		} else if ((ni->ni_ath_flags & IEEE80211_NODE_FF) &&
736 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
737 		    m->m_pkthdr.len >= 3*FF_LLC_SIZE) {
738 			struct llc *llc;
739 
740 			/*
741 			 * Check for fast-frame tunnel encapsulation.
742 			 */
743 			if (m->m_len < FF_LLC_SIZE &&
744 			    (m = m_pullup(m, FF_LLC_SIZE)) == NULL) {
745 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
746 				    ni->ni_macaddr, "fast-frame",
747 				    "%s", "m_pullup(llc) failed");
748 				vap->iv_stats.is_rx_tooshort++;
749 				return IEEE80211_FC0_TYPE_DATA;
750 			}
751 			llc = (struct llc *)(mtod(m, uint8_t *) +
752 				sizeof(struct ether_header));
753 			if (llc->llc_snap.ether_type == htons(ATH_FF_ETH_TYPE)) {
754 				m_adj(m, FF_LLC_SIZE);
755 				m = ieee80211_decap_fastframe(ni, m);
756 				if (m == NULL)
757 					return IEEE80211_FC0_TYPE_DATA;
758 			}
759 		}
760 #undef FF_LLC_SIZE
761 		ieee80211_deliver_data(vap, ni, m);
762 		return IEEE80211_FC0_TYPE_DATA;
763 
764 	case IEEE80211_FC0_TYPE_MGT:
765 		vap->iv_stats.is_rx_mgmt++;
766 		IEEE80211_NODE_STAT(ni, rx_mgmt);
767 		if (dir != IEEE80211_FC1_DIR_NODS) {
768 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
769 			    wh, "data", "incorrect dir 0x%x", dir);
770 			vap->iv_stats.is_rx_wrongdir++;
771 			goto err;
772 		}
773 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
774 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
775 			    ni->ni_macaddr, "mgt", "too short: len %u",
776 			    m->m_pkthdr.len);
777 			vap->iv_stats.is_rx_tooshort++;
778 			goto out;
779 		}
780 #ifdef IEEE80211_DEBUG
781 		if (ieee80211_msg_debug(vap) || ieee80211_msg_dumppkts(vap)) {
782 			if_printf(ifp, "received %s from %s rssi %d\n",
783 			    ieee80211_mgt_subtype_name[subtype >>
784 				IEEE80211_FC0_SUBTYPE_SHIFT],
785 			    ether_sprintf(wh->i_addr2), rssi);
786 		}
787 #endif
788 		if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
789 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
790 			    wh, NULL, "%s", "WEP set but not permitted");
791 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
792 			goto out;
793 		}
794 		if (bpf_peers_present(vap->iv_rawbpf))
795 			bpf_mtap(vap->iv_rawbpf, m);
796 		vap->iv_recv_mgmt(ni, m, subtype, rssi, noise, rstamp);
797 		m_freem(m);
798 		return IEEE80211_FC0_TYPE_MGT;
799 
800 	case IEEE80211_FC0_TYPE_CTL:
801 		vap->iv_stats.is_rx_ctl++;
802 		IEEE80211_NODE_STAT(ni, rx_ctrl);
803 		goto out;
804 	default:
805 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
806 		    wh, "bad", "frame type 0x%x", type);
807 		/* should not come here */
808 		break;
809 	}
810 err:
811 	ifp->if_ierrors++;
812 out:
813 	if (m != NULL) {
814 		if (bpf_peers_present(vap->iv_rawbpf) && need_tap)
815 			bpf_mtap(vap->iv_rawbpf, m);
816 		m_freem(m);
817 	}
818 	return type;
819 #undef SEQ_LEQ
820 }
821 
822 static void
823 wds_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
824 	int subtype, int rssi, int noise, u_int32_t rstamp)
825 {
826 	struct ieee80211vap *vap = ni->ni_vap;
827 	struct ieee80211com *ic = ni->ni_ic;
828 	struct ieee80211_frame *wh;
829 	u_int8_t *frm, *efrm;
830 
831 	wh = mtod(m0, struct ieee80211_frame *);
832 	frm = (u_int8_t *)&wh[1];
833 	efrm = mtod(m0, u_int8_t *) + m0->m_len;
834 	switch (subtype) {
835 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
836 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
837 	case IEEE80211_FC0_SUBTYPE_BEACON:
838 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
839 	case IEEE80211_FC0_SUBTYPE_AUTH:
840 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
841 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
842 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
843 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
844 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
845 		vap->iv_stats.is_rx_mgtdiscard++;
846 		break;
847 	case IEEE80211_FC0_SUBTYPE_ACTION:
848 		if (vap->iv_state != IEEE80211_S_RUN ||
849 		    IEEE80211_IS_MULTICAST(wh->i_addr1)) {
850 			vap->iv_stats.is_rx_mgtdiscard++;
851 			break;
852 		}
853 		ni->ni_inact = ni->ni_inact_reload;
854 		if (ieee80211_parse_action(ni, m0) == 0)
855 			ic->ic_recv_action(ni, frm, efrm);
856 		break;
857 	default:
858 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
859 		     wh, "mgt", "subtype 0x%x not handled", subtype);
860 		vap->iv_stats.is_rx_badsubtype++;
861 		break;
862 	}
863 }
864